It is known that some types of lesions, such as corneal lesions or chronic ulcerative lesions, are considerably difficult to heal and, for this reason, not only result in continuous discomfort for the patients but also in high health costs.
Some modern health care methods envisage the use of platelet preparations, such as platelet concentrates or platelet gels, in order to treat the aforementioned lesions.
Platelet concentrate, also known as PRP (Plasma Rich in Platelets), is obtained by centrifuging a blood sample, while platelet gel, autologous or homologous, is generally obtained by adding activating substances such as thrombin and batroxobin, to a platelet concentrate. The platelet gel preparation can be made both before and at the time of use, by mixing the suitably prepared platelet concentrate with the aforementioned activating substances.
These platelet preparations contain numerous and important growth factors that stimulate the fundamental biological mechanisms for tissue repair and regeneration.
Generally, to treat corneal lesions, the platelet concentrate is used fresh and/or frozen, while chronic ulcerative lesions and, generally speaking, tissue regeneration are treated with platelet gel.
More in particular, the method used to date for the preparation of samples of platelet concentrate to be used as collyrium envisages filling a duct (dialysis intravenous line) made of plastic material and closing such duct, e.g. by sealing, in correspondence to a plurality of areas arranged in succession the one to the other and separated the one from the other, in such a way as to form a plurality of closed units.
These units are then opened, before being used, by cutting one of their respective extremities, e.g., using a pair of scissors, in such a way as to make their contents available for use.
The units of platelet concentrate can contain a single, daily or weekly dose, and their contents must be preserved at a temperature of around −40° C. before use and at around +4° C. for the first and the subsequent therapeutic uses (in the case of daily or weekly doses).
Generally speaking, in particular in the case of patients who are medicated at home, the open units of platelet concentrate are kept inside the domestic refrigerator which also contains food products.
These units, containing platelet concentrates made using the method of known type described above, have a number of drawbacks.
More in particular, the units of known type are not easy and safe to use and do not allow complying with the hygienic-health requirements of applicable laws and those of certification institutes for hemoderivatives.
In fact, opening these units with a pair of scissors or the like results in residues of organic material contained in the relative unit remaining on the cutting area of such scissors, with the consequent risk of contaminating the contents of the other units subsequently cut using the same pair of scissors.
This obviously creates the risk of the platelet content of the units cut by means of a pair of scissors already previously used being polluted by the residues remaining on the scissors themselves, thus compromising its therapeutic properties and above all considerably increasing the risk of secondary infections being caused in patients who are already immunodepressed and on an already compromised organ.
Another drawback of known units for the containment of platelet concentrate consists in the fact that, once opened, they do not allow the safe storage of their contents, which should instead be stored in an environment that is as sterile as possible.
In fact, as described above, the units containing daily or weekly doses of platelet concentrate are then generally stored inside normal domestic refrigerators, where they could be contaminated (including on the outside) by bacteria and microorganisms present on food products (eggs, dressed-pork products, vegetables . . . ) contained therein and by the bacterial flora, fauna and fungi normally present inside said environment.
More in detail, the containment units of known type, once opened, remain accessible from the outside, and consequently their contents could be contaminated by external agents.
Another drawback still of the containment units of known type consists in the fact that they do not make it possible to check the dosage of the platelet concentrate to be used.
Two known connection devices are described by DE 20203154 and by U.S. Pat. No. 4,397,442.
DE 20203154 describes a connection element for connecting a bag to an infusion line. This connection element comprises a main body, inside which is defined a flow duct for a liquid, closed at one extremity by a closing element removable by tearing off. The opposite extremity of such main body is obstructed by a cap, removable to allow access from outside.
More in particular, to use the connection element subject of DE 20203154, the closing element must first of all be removed so as to open the flow duct and be able to connect the relative extremity of the main body to a containment bag, and remove the cap from the opposite extremity to allow the treated liquid to flow off.
Once the closing element is removed from the main body, it is no longer possible to reposition it on the latter, while the cap fitted at the opposite extremity of the main body has the sole purpose of obstructing the flow duct and must necessarily be removed to allow the flow of the treated liquid and therefore the filling of the relative bag.
The connection device described by DE 20203145 does not appear very easy to use inasmuch as it necessarily requires the removal of the closing element and of the cap from the main body before use and, once the relative bag has been filled, requires the removal of the infusion line from the main body and the closing of the flow duct by means of the cap itself. During bag filling, the closing cap is therefore separate and released with respect to the connection device, with the risk of its being lost or in any case not easily identifiable in case of need.
Furthermore, the realisation of the connection device subject of DE 20203145 requires the separate realisation of the main body and of the closing cap, for example using two separate moulds, and this means that manufacture is complicated and costly.
U.S. Pat. No. 4,397,442 describes a valve device suitable for allowing/preventing the flow of a liquid through it and associable with a containment bag.
More in particular, this valve device comprises a fixed portion and a mobile portion.
The fixed portion and the mobile portion are both tubular shaped and define a flow duct for the transit of the treated liquid. The fixed portion also has a protuberance suitable for being inserted inside the mobile portion to obstruct the liquid flow duct.
The mobile portion associated integral with the fixed portion, in turn comprises a flexible flange suitable for permitting the reciprocal movement of such portions.
The movement of the mobile portion with respect to the fixed portion makes it possible to modify the section of liquid flow duct, choking the flow of treated liquid. The mobile portion thus moves between two extreme positions, one closing the flow duct and one opening the flow duct to maximum extent, passing through a plurality of intermediate positions, each of which corresponds to a different section of the duct itself and, therefore, to a different liquid flow rate.
This valve device, as such, does not allow tilling a container easily and quickly because the mobile part must be manually moved to an open position and kept this position during the entire procedure to allow the flow of the liquid.
Furthermore, this valve device does not ensure either the seal or the safe preservation of the liquid once the bag associated with the device itself has been filled, inasmuch as the accidental movement of the mobile portion can cause the opening of the flow duct and, therefore, the escape of the liquid. The use of a removable safety cap further complicates the realisation and use of such valve device, inasmuch as it requires the control of a further component separate and independent of the others.